Method of and apparatus for forging wheels and parts thereof



Sept. 28, 1926.

L60Ll95 c. 1.. WILBER METHOD OF AND APPARATUS FOR FORGING WHEELS AND PARTS THEREOF Filed June is, 1921 2 Sheets-Sheet 1 -n wv anmmmmw My m Sept, 28, 1926.

C. L. WILBER AND APPARATUS FOR FORGING METHOD OF Filed June 15. 1921 Inf nt) I [Zyj-Z Zlilfier l M Y u am W H J13; 1 1 U3 Fatented Sept. 28, 1926.

CARL L. WILBER, OF DETROI'I, MICHIGAN, ASSIGNOR 'IO JEFFERSON FORGE PRODUCTS COMIANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

METHOD OF AND APPARATUS FOB'FOBGING WHEELS AND PARTS THEREOF.

Application filed June 13, 1921.

The general object of my invention is to provide a satisfactory and economical method and means for forging complete vehicle wheels or parts thereof, to produce in a single piece drop-forging an entire wheel that may include felloe, lugs, spokes, center disk, hub, brake drum 'andreinforcing webs (thus making the wheel available as the rear Wheel of an automobile) or that may include any less number of the stated parts or their equivalents. a

Among the important desiderata in such work as that to which my present invention is applied are: certainty of operation, minimizing spoila e in manufacture; rapidity and ease in the performance of each operation; minimization of the number of operations; avoidance and correction of forging strains in the metal to produce a balance product that will not tend to warp or distort from shape; securing of uniformity of texture through like portions of the product and uniformity of metal flow in requisite quantity to the difiierent areas or zones of the product during the forging operation; avoidance of necessity for difficult andexpensive finishing operation such as straightening of the product or correction of manufacturing errors or failures; provision of simple and eflicient apparatus for the practice of the method hereinafter described and the provision of a method and means available for the manufacturing of wheels of artistic design and affordingsuch disposition of metal as will give maximum overall strength with minimum weight.

All of these desiderata I attain through my invention, and while for purposes of disclosure I will particularly point out the availability of my invention for the making of a wheel-structure of considerable compleXitythat is to say. the making of a rear wheel for an automobile embodying in the integral forging afelloe. a hub body and a brake drum bodyit will be understood by those skilled in the art that in its broader aspects my invention is not restricted to the making of this particular type of wheel. but on the contrary is susceptible of wide application in the making of other and simpler wheel structures or wheel parts as well as pulleys, flywheels, etc.' p

The product resulting fronrtlie within described practice e-l my have? Serial No. 477,083.

forge-finishing the blank and the finishforged blank; Fig. 5 represents diagrammatically a. tong-hold removing operation; and Fig. 6 represents diagrammatically a blank trimming means and the'trimmed completed blank or forging.

Forconversion of a'simple rolled-metal slab as shown in Fig. 1 into a forged wheelform of a relatively complex nature as shown in Fig. 6, wholly by forging and punching operations I employ specially designed tools in the way of blocking dies, blocked-blank punching dies, finished-forging dies, tong-hold removing dies, and trimniing dies, all used in connection with stand ard steam drop-forging hammers, punch presses and heating furnaces such standard devices being found in all forge-shops and needing no detailed description. The preferred sequence ofoperations and the special tools therefor I will now describe, but it will be understood that, while it is advantageous to follow the full course of operations so to be described; changes of method and of apparatus may be made insome particulars without departure (by reason of retentlon of other procedural steps and apparatus that I novelly and advanta eously provide) from'the spirit and scope of my invention.-

'In the practice indicated in the drawings I start with a rolled steel slab A; that preferably is a rather-thick block of generally rectangular shape containing some excess of material above ultimate requirement and provided with a tong-hold or tail 6. This tong-hold it may here be understood; is preserved throughout the sequence of operations until the metal has been heated for the last time, so as to" permit facile handling I of the article with usual tongs at all necessary stages of development, and all forging dies and punching dies that are em ployed before the tong-hold or tail 6 is removed have suitable marginal openings or clearances for the reception thereof. All forging operations are effected by mated, horizontal dies, recessed in their confronting surfaces, and operated by a standarc steamhammer.

The slab A is first subjected to a block forging operation to secure a preliminary distribution of the metal into zones of different thicknesses, that roughly speaking, will be proportional to the demand for metal to constitute the different circular zones of the completed wheel or part of a wheel; namely, in the illustrated instance, the f'elloe zone, spoke zone and center-body zone of the wheel. The slab A is heated to proper forging temperature, say approximately 1900 degrees F., with a slow tire and the hot blank 11 is forged between the upper and lower dies B, B. respectively keyed to the ram and the sow-block anvil of a suitable hammer (not shown) to bring the blank to the blocked form shown at A (Fig. 9). Generally speaking, the blocked blank A should take circular form with a felloe mass (4 of substantial thickness (i. e., measurement transversely to the plane of the wheel) approximating the fell'oe or rim width; with av thinner spokezone web a of approximately spoke-thickness or somewhat more; and with center-body mass a that should preferably be closely figured in metal con-- tent to the requirements of the finished center-body. lVhere hub and brake-drum formation is desired, an annular flange mass a is formed on one side of the blank and the center of the blank is thickened preferably on both sides of the blank to form arelatively deep hub-mass a.

To produce this specific block-formation the complemcntal dies B, B have, in addition to the tong-hold clearances t, the complemental felloe grooves 72 and 7), spokezone surfaces Z1 and b, and hub-mass reccs' es and b the latter recesses being surrounded, in the upper die B by the annular flange-recess 7).

It is important, in the formation of the particular block-blank A shown, that the metal mass a for hub-formation shall not exceed the demand for metal to consti ute the final hub-block and it is desirable that the entire center-body mass shall not contain excess metal, but that, to the contrary, it shall be quite accurately figured as to content or tend slightly toward deficiency in metal-mass. Also it is preferable that the spoke-web shall have its minimum thickness adjacent to the center body and shall be slightly thickened toward the outermost margin, any surplus of stock in the block-blanking being forced toward the margin and utilized in felloeformation or marginally extruded from the die-cavities. This special care in the proportioning of center-body cavities in block forming is necessary only when the forged center is to be solid, as when a hub-block is desired, so as to prevent trapping: of excess metal that may cushion the subsequentlyemployed dies. In general it will be understood that, since this blocked-forged blank represents only an intermediate stage in development of the completed article, it is not essential that the blocked-blank A. shall have absolute regularity of contour nor the precise diameter of the finished product. The greater the approximation of regularity and uniformity of contour that may (without undue expense) be had in the blocking of the blank, however, the easier and more uniform are made subsequent operations there on and therefore special provision for the rapid and uniform blocking is to be preferred. As illustrated the shaping of the dies is such as to give a quick flow of metal toward the periphery throughout the spokezone and to afford smooth inclines or curves to insure desired flow of metal to the center body Zone. Of course if integral hub structure or integral brake-band flange be not required the dies will be accordantly changed in conformation.

Before finish-forging this blocked blank I remove surplus metal from the zone or zones that, by reason of intended ultimate perforation, may best suffer the removal and that, by virtue of position, will afford best relief areas for escape of residual excess of metal in the finish-forging operation, all in accordance with the demands of the wheel or wheel-structure ultimately to be produced. In respect of the particular construction shown I preferably remove the excess metal from the spoke-zone and preferably perform this operation in the manner illustrated in Fig. 3. The blocked blank is laid on die 10 carried by trimmer-shoe 11 that is bolted to the bed-plate of an ordinary much-press and such blank is struck by the punching die 12, the cutting projections 1 -3 of which. registering with openings 1 1- of a stripper plate 15 and registering with the receptive openings 16 of the lower die. strike out segments of the spoke-zone of the bla k so converting it to the spoked-blank form indicated at A in Fig. 3. The stripper plate 15 may be normally raised by spring sustained stop-guides 17 to stand at the upper end of the very limited range. of motion and it serves to strip the blank from the cutting projections 13 as the upper die rises. This punching operation may well be performed while the blank is still relatively hot. and should of course leave the spoked-blank A? with spoke-strips a that, in number and angular position, correspond with the demands of the finished wheel. Although throughout cord'antly with the metal disposition to be made in the finished forging, substantial deviation, intentional or otherwise, from this ideal may readily be overcome in the finishing operations to be described, and indeed the spoked, blocked blank may be produced in other ways.

The punched-blank or spoked-blank A should again be brought to forging temperature and then is submitted-to the operation of the forge-finishing dies C, C, that of course are fixed respectively in the ram and the sow-block of a suitable hammer. These dies have mated or coinplemental circular and radial cavities, with flash-clearances, and gutters, accurately to bring the properly-sized and shaped speked-blank to finished contour throughout all of the cavityreceived portions, that is to say, to bring it to finished shape except for flashes, of extruded, excess metal and for the tong-hold. In the specific construction shown the dies C, C are preferably divided on such a line.

that the recess of the lower die provides the entire forming face for the exterior surface of the felloe in order that, desirably,

the felloe or rim may present a frustoconoidal exterior, and marginally beyond both felloe-recesses 0 and 0 of the upper and lower dies annular gutters 0 are provided, while along the inner margins of the felloe-grooves of the dies certain lug-forming recesses C may be made. here spokes of concave-convex or parti tubular crosssection are desired complemental spokechanneling projections c and spoke grooves 0 may be provided in the upper and lower dies, these merging into the appropriately formed surfaces for forming the centerbody. Thus upper die C is shown annularly recessed at 0 for the formation of a brakedrumfiange and as centrally recessed as at c for the formation of a hub-part while the lower die is recessedonly as at 0 for a hubpart. Grooves e in the upper die may provide for the formation of radial ribs on the wheel between the hub and the brake-drum flange. Shallow escape-tolerance for the ex trusion of a flash throughout the area between spokes is provided between the dies and it is my preference that the central portion of each interspoke segment be recessed or guttered as at 0 Thus, in the finishforged blank A as shown in Fig. t a flash, preferably thin at its line of juncture with the body of the casting and thicker at a li tle distance from said body borders the feline and also borders entirely each segmental interspace between spokes, as indn cated respectively at a and a 1n F1 it.

' lt will' be understood that according to the specifications of different wheels or wheel-structures less than the full device shown, details may vary from those above described, but in'general it is desirable that the finishiiW-die contours should afford ample facility for flow of metal to those Zones (such as the rim zone) where excesses of metal may best be taken care of and find escape as flashes; and that flashes shall be formed as a thin strengthening and stiffening web, lying in the plane of the work, in those areas that are ultimately to be open spaces and preferably may also form a web about the perimeter of the forging. Thus the blank A as fashioned in the finishing dies. embodies the complete contour of the finished article but with the addition of the flashes aforesaid. It is to prevent pocketing ortrapping of metal in the central cavities, with resultant detriment in preventing the blank from being properly reduced by dies C, C, that careful proportioning of the central mass of the blocked blank is most desirable.

The forge-finished blank, A with its flash-webs undisturbed, is annealed before any further shaping operation takes place, in order to relieve the metal of forgingstresses, and warping tendencies and in order to prepare it for easy trimming; and it is noteworthy that notwithstanding the tortuous eflect that is inevitable in widespreading, re-massing and reducing of metal to such extremes as are represented by the formation of the described automobile wheel or in any such forging operations as above described, the flash-carrying blank in nearly every instance stands annealing without any such warping or loss of shape as would require re-shaping. This highly desirable and economical characteristic I ascribe not merely to the uniformity of action in the forging, but in very material measure to the presence of the highly-condensed flash-web lying in what I may term the plane of work, that is to say, in the generally flat or slightly-dished conformation into which the forge-finished blank has been brought.

The annealed blank may now be allowed thoroughly to cool with its flash-web intact, and then the blank is subjected to a cold trimming. First its tong-hold may be removed by a punching operation as indicated in Fig. 5. In this operation the felloeperimeter is brought into contact with two gauge-pins on a die-plate 31 whereon the tong-hold and wheel felloe are firmly seated.

' Such plate has a punch-receptive opening 32 shorter than the length of the tong-hold and with its front edge conforming to the are of the felloe. The tong-hold, thus receiving support on both sides of the orifice 32, is struck by the 31inch 33 that corresponds in shape with orifice 32 and thus is sheared off,

made

is \t 4 ll L trimmed to the final condition shown in Fig. 6 preJl'crabl by cutting mechanism as therein shown. The flash-carrying blank is laid on the shoe 4.0, which is bolted to the bed-frame plate of a punch-press, this shoe having: deep circular and radial recesses i1 and 42, appropriate to receive the wheelproper and l arine' fixed circumferential illl. segmental cutting dies -33 and 1A, respectively these conforming to the perimeter of the felloe and to the spoke interspaces to be trimmed. So positioned the blank is struck by the punch -t5 that is shaped smoothly to the uppermost contours of the wheel-proper and throughout its perimeter and along the spoke intcrspaces to eoact with the die surfaces of the shoe thereby to shear the wheel from the flashes and to force the wheel down into the open spaces of the shoe. Specifically e6 indicates the lelloe-trimmino edge; at? the spoke-fitting surfaces and 5 the center, grooved to fit with the wheel center-body. Spring-pressed retaining: points 50 protruding from the spoke-interspace portions of tl e punch strike upon, and retain in position the inter-spoke flashes and a lift block 51, arranged in the peripheral recess of the shoe 5 .0 and carried in vertical reciprocation by the rod $5 of the punch t5, serves, upon the movement of the punch t5 away from the shoe 40, to lift the finished wheel out of the recess for removal, any well known and suitable manner of coupling between the rods :45 and lift block 51 being employed to permit of this and the opposite movement of the punch die. For example, the rods 45" ma slidablv engage the lift block 51 in such a manner that the punch die may be fully moved upon the shoe .0, and. during its reverse movement, the lift block ma)- be picked up by the rods 45 and the finished wheel raised as explained. i find that this finish-punching operation ha a beneficial straighteniin; tendency, cttectually trueing' in the flat wheels that may be slightly out of true when presented to the press.

The operations heretofore described conr plete the wheel subject only to final machining operations such as the final surfacing of a brakedru1n. boring out of the hub surfacing the felloe, tapping; of apertures for desired atta :hinents, etc, and the speed and facility with which the substantially complete unitary wheel can be produced renders its nnmufjacture one of most desirable economy.-

I find it to be desirable and economical, and therefore prefer, to make the wheel from slab to the a iistantiallv complete form shown by the to 0 ng and punching method described. because all ipcrations, and particularly the n'eliininam ones to brin the blanl into its intermed ate block-it)! if and punched state, may be perfornud in quantit; with rapidity and low expense. and the successive forging operations are beneficial, in insuring a homogeneous, flawless lzod) of metal throughout the structure with s rial fineness of grain and toughness in the re tivel thin sections such, particularly as the spoke sections and the center-dirk section b tween the hub and lateral llillfifi (heretofore referred to as a brake-drum lla hat may be an) strengthcuin; thin; i however; 't'ezsible with retention of part oi the benefits of my invention, to operate on t cast blank in any s 'ail'e of development up to that represented aaove as a blocktorged and spoke-punched blank: and in other respects port ons of the full pro ess rnd apparatus above set forth may be emlojfed with corresponding" rcl'ention of cuelits and at, iililtlflOS through the utilizaion o 'l eatures of nrv invention.

method of forging a wheel strucconsis s in block-forein; an in of sub, utiallv uniform thicktribnte the metal into a pluralit ar ;zoncs of dili'ercnt thicl-tncsses aroiziinating, in metal contents, the reireincuts oi? corr spondingr portions of the imate article; punching; the blocked- .ink to present lJtOFRpOlU openings: therecr flIHSll-l no the spoked blank into i i presenting; appropriatelv contoured cir: .ilar zone renter thickn es and ra'li- 1 lies ol less tpticknt said spokes roub v thin intermed ate flashes: annealing: the forge-tinished blank. and trimming sa d blank to remove the inter-spoke flashes.

2. The proves o'l forging a wheel structure which consists in block-forging; an initial blank of appropriate thickness to distribute the metal into a pluralit of circa lar zones of dillereut' thicknesses approximating: in metal contents the requirements of cm'respondiin: zones oi the ult mate a ticle: punching out spoke-int'erspzn-rs of said blank: linisln'torgying the epol-ted-ljilanl-t into form presenting" approprialel v contoured circular zones of greater th ckness and radial spokes of less thirkne=- w th the spoke iuterspaces bordcre-l bv thin tlashcs: annealing); the forced-tiuished flash-carrying blank: and col lpunching1 the flashes from said blank.

I). The art oil forging rimmed wheel-structures which consists in perforating a metal hlank wi its mar ns to provide openings in position corresponding; with spokw O nectcd 'litl interspaces; forging said blank to provide rim and spoke formations with thin flashes bordering the spoke interspaces; annealing the forged flash-carrying blank; and thereafter trimming the blank for removal of the flashes.

4:. The art of forging a wheel structure to present a relatively deep annular felloe, an annular flanged center-body and connecting spokes that consists in block-forging a slab between recessed dies into form presenting a relatively thick zone approximating the metal demand of the felloe-zone, a thinner spoke-zone, and a flanged centerzone; punching the spoke-zone to provide approximations of spoke-interspaces, finishfor 'ing the punched-blank between recessed dies toleave in the spoke interspaces and around the rim thin horizontal flashes; an nealing the flash-carrying blank and punching the flash from the blank.

5. The method of forming a wheel structure which consists in subjecting a metal slab to block-forging between recessed dies to circumferentially expand the metal and distribute it into approximately circular zones of varying thicknesses, including a central zone closely approximately the requisite metal-content of the central zone of the finished article and a surrounding zone of less thickness; punching the thinner zone surrounding said central zone to form spokeinterspacesgsubjecting said spoked blank to finished-towing between recessed dies to produce ultimate forged-contours including a center-body and separated thin radial spokes, these bordered by relatively thin V flashes in the plane of the work, annealing the flash-carrying blank, and cold punching the forge-finished blank thus produced to ultimate contour.

6. The method of forging a wheel structure which consists in subjecting a blank that presents a circular zone of relatively greater thickness and radial spoke formations of less thickness to finish-forging operation between recessed dies to, produce a forge-finished blank with relatively thin flashes in the plane of the work bordering the spoke-interspaces, annealing the flashcarrying blank, and trimming the flashes from the finishing blank thus produced.

7. Steps in the art of forging rimmed wheel structures which consist in subjecting a blank, that presents a relatively thick circular felloe-zone and relatively thin radial spoke-formations and a tong-hold protruding from thefelloe to finish-forging between recessed dies; subjecting the forge-finished blank to punching away of the tong-hold with the end of the tong-hold and the connected felloe respectively supported oppositely beyond the punching instrumentality, and thereafter subjecting the rim to a trimming operation.

8. An instrument-set for making forged wheels comprising mated block-forming dies having center-bocy recesses closely approximating ultimate-contour content, spoke zone recesses and deeper felloe recesses; mated finish forming dies having center-body recesses of desired contour, radial spoke recesses, a felloe recess and spoke-and-felloebordering flash-spaces and gutters; and blank-punching dies having flash-cutting surfaces conforming throughout to the spoke-and-felloe contours.

CARL L. WILBER. 

